CN219164214U - Leakage protection circuit - Google Patents

Abstract

The utility model relates to a leakage protection circuit, and belongs to the technical field of protection circuits. The circuit comprises: the triggering module responds to leakage current generated between the live wire and the zero wire and outputs a triggering signal; the control module is used for responding to the trigger signal and outputting a control signal; and a switch disposed in the line between the live wire and the neutral wire and the load, the switch being opened in response to the control signal.

Description

Leakage protection circuit

Technical Field

The utility model relates to the technical field of protection circuits, in particular to a leakage protection circuit.

Background

At present, the current at the two ends of the live wire and the zero wire are generally equal in magnitude and opposite in direction. In the case where the sum of the currents between the live and neutral conductors is not zero, it can be considered that a leakage current is generated between the live and neutral conductors. In the prior art, the leakage protector is generally directly utilized to disconnect the circuit under the condition of circuit leakage, so that the precision is lower.

Disclosure of Invention

The utility model aims to solve the problem of lower precision caused by disconnecting a line under the condition of line leakage by directly utilizing a leakage protector, and provides a leakage protection circuit.

According to an aspect of the present utility model, there is provided a leakage protection circuit comprising:

the triggering module is used for responding to leakage current generated between the live wire and the zero wire and outputting a triggering signal;

the control module is used for responding to the trigger signal and outputting a control signal; and

and the switch is arranged in a line between the live wire and the load as well as between the zero wire and the load, and is opened after responding to the control signal.

Optionally, the triggering module comprises a current transformer, and an iron core of the current transformer is sleeved on a line between the live wire and the zero wire and a load;

the iron core of the current transformer responds to leakage current generated between the live wire and the zero wire, so that the winding of the current transformer outputs a trigger signal.

Optionally, the control module comprises a leakage protector and a thyristor sub-module;

the leakage protector responds to the trigger signal and outputs a conduction signal;

and under the condition that the thyristor submodule is turned on after responding to the on signal, the leakage protector outputs a control signal.

Optionally, the thyristor submodule includes a first thyristor and a second thyristor;

the leakage protector responds to the trigger signal and respectively outputs a first conduction signal and a second conduction signal;

the leakage protector outputs a control signal in a case where the first thyristor is turned on in response to the first on signal and the second thyristor is turned on in response to the second on signal.

Optionally, the circuit further comprises a first resistor and a first capacitor connected in series, and a second resistor and a second capacitor connected in series;

the other end of the first resistor is connected with the anode of the first thyristor, and the other end of the first capacitor is connected with the cathode of the first thyristor;

the other end of the second resistor is connected with the anode of the second thyristor, and the other end of the second capacitor is connected with the cathode of the second thyristor.

Optionally, the leakage protector model is M54123L.

Optionally, the switch is a relay, and a coil of the relay responds to the control signal so that a contact of the relay is opened;

the contact of the relay is arranged in a line between the live wire and the zero wire and the load.

Optionally, in a case where the control module outputs a control signal, the switch receives the control signal through a diac and opens.

The utility model has the technical effect that the trigger module can output the trigger signal under the condition that leakage current is generated between the live wire and the zero wire. The control module can output a control signal after receiving the trigger signal, and the switch can be disconnected after receiving the control signal. Through setting up trigger module, detect leakage current more sensitively for control accuracy is higher, in order to play the effect of protection load and circuit.

Other features of the present utility model and its advantages will become apparent from the following detailed description of exemplary embodiments of the utility model, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description, serve to explain the principles of the utility model.

Fig. 1 is a circuit diagram of a leakage protection circuit in an embodiment of the present application.

Reference numerals:

a circuit 100;

a trigger module 10;

a control module 20; a thyristor module 21;

and a switch 30.

Detailed Description

Various exemplary embodiments of the present utility model will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present utility model unless it is specifically stated otherwise.

The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the utility model, its application, or uses.

Techniques and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

A specific description of a leakage protection circuit according to an embodiment of the present application is provided below with reference to fig. 1.

An overvoltage protection circuit for security monitoring according to one embodiment of the present application, the circuit 100 includes: the trigger module 10 is used for responding to leakage current generated between the live wire and the zero wire and outputting a trigger signal by the trigger module 10; the control module 20, the control module 20 responds to the trigger signal, output the control signal; and a switch 30, the switch 30 being arranged in the line between the live and neutral wires and the load, the switch 30 being opened in response to a control signal.

Specifically, in the event of leakage current between the live and neutral wires, the trigger module 10 may output a trigger signal. The control module 20 may output a control signal after receiving the trigger signal, and the switch 30 may be turned off after receiving the control signal. By arranging the trigger module 10, the detection leakage current is more sensitive, so that the control precision is higher, and the functions of protecting loads and circuits are achieved.

In one embodiment, the triggering module 10 comprises a current transformer, and an iron core of the current transformer is sleeved on a line between the live wire and the zero wire and the load; the iron core of the current transformer responds to leakage current generated between the live wire and the zero line, so that the winding of the current transformer outputs a trigger signal.

Specifically, as shown in fig. 1, the current transformer may be a zero sequence transformer ZCT1, and correspondingly, an iron core of the current transformer is sleeved in a line between a live wire and a zero line and a load, and a primary winding of the current transformer may be energized to enable a secondary winding (i.e., a winding) of the current transformer to obtain a trigger signal and output the trigger signal to the control module 20. The trigger signal may be an induced voltage. In other words, by providing the current transformer, a magnetic field can be formed by using leakage current generated between the live wire and the neutral wire to output a trigger signal to the control module 20, so as to reduce power loss caused by the trigger module 10 accessing the above-mentioned lines.

In one embodiment, the control module 20 includes a leakage protector and thyristor sub-module 21; the leakage protector responds to the trigger signal and outputs a conducting signal; in the case where the thyristor module 21 turns on in response to the on signal, the leakage protector outputs a control signal.

Specifically, as shown in fig. 1, the 1 end of the leakage protector U2 may be connected to one end of the winding, the 2 end of the leakage protector U2 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the other end of the winding. The capacitor C7 and the resistor R3 can be connected between the windings in a bridging way, and the filtering effect can be achieved. The leakage point protector U2 may output a turn-on signal to the thyristor sub-module 21 in response to the trigger signal output from the winding, and the thyristor sub-module 21 is turned on after receiving the turn-on signal, so that the leakage point protector U2 may output a control signal to the switch 30, so as to disconnect the line between the live wire and the neutral wire and the load in case that a leakage current is generated between the live wire and the neutral wire.

In one embodiment, the thyristor sub-module 21 comprises a first thyristor and a second thyristor; the leakage protector responds to the trigger signal and respectively outputs a first conduction signal and a second conduction signal; the leakage protector outputs a control signal in a case where the first thyristor is turned on in response to the first on signal and the second thyristor is turned on in response to the second on signal.

Specifically, as shown in fig. 1, the G pin of the first thyristor Q1 is connected to the 7 terminal of the above-mentioned leakage protector U2, and a capacitor C6 is further connected between the 7 terminal and the 6 terminal of the leakage protector U2. The 8 ends of the leakage protector U2 are connected with a resistor R5, the other ends of the resistor R5 are connected with the anode of a diode D1, and the cathode of the diode D1 is connected with the G pin of a second thyristor Q2. The anode of the first thyristor Q1 is connected with the cathode of the second thyristor Q2, and when the first thyristor Q1 receives the first conduction signal and then turns on and the second thyristor Q2 receives the second conduction signal and then turns on, the leakage point protector U2 can output a control signal to the switch 30. In other words, by connecting the first thyristor Q1 and the second thyristor Q2 in series, the situation that the first thyristor Q1 or the second thyristor Q2 is broken down due to the excessively high voltage can be effectively reduced.

In one embodiment, the circuit 100 further includes a first resistor and a first capacitor connected in series, and a second resistor and a second capacitor connected in series; the other end of the first resistor is connected with the anode of the first thyristor, and the other end of the first capacitor is connected with the cathode of the first thyristor; the other end of the second resistor is connected with the anode of the second thyristor, and the other end of the second capacitor is connected with the cathode of the second thyristor.

Specifically, as shown in fig. 1, one end of the first resistor R7 is connected to the anode of the first thyristor Q1, the other end of the first resistor R7 is connected to one end of the first capacitor C8, and the other end of the first capacitor C8 is connected to the cathode of the first thyristor Q1. One end of the second resistor R6 is connected with the anode of the second thyristor Q2, the other end of the second resistor R6 is connected with one end of the second capacitor C9, and the other end of the second capacitor C9 is connected with the cathode of the second thyristor Q2. By arranging the first resistor R7, the second resistor R6, the first capacitor C8 and the second capacitor C9, the breakdown of the first thyristor Q1 and the second thyristor Q2 due to the excessively high voltage can be effectively reduced.

In one embodiment, the leakage protector model is M54123L.

Specifically, as shown in fig. 1, the leakage protector U1 is of the model M54123L, the leakage protector U1 can output a turn-on signal by a voltage difference between the 1 terminal and the 2 terminal, it is easy to realize that the control switch 30 is turned off in the case of generating a leakage current, and the power consumption is low.

In one embodiment, where the control module 20 outputs a control signal, the switch 30 receives the control signal through a diac and opens.

Specifically, as shown in fig. 1, the 1 terminal of the diac DB1 is connected to the anode of the second thyristor Q2, the resistor R1 and the resistor R2 are connected in series, the other terminal of the resistor R1 is connected to the 1 terminal of the diac, and the connection point between the resistor R5 and the 8 terminal of the leak point protector U2 is connected to the other terminal of the resistor R2. The end 4 of the diac DB1 is connected with the cathode of the first thyristor Q1, the capacitor C2 and the capacitor C3 are connected in series, the connection point of the resistor R5 and the resistor R2 is connected with the other end of the capacitor C2, and the other end of the capacitor C3 is connected with the end 1 of the leakage point protector U2. The connection point of the capacitor C2 and the capacitor C3 is connected with the 3 end of the leakage protector U2 and then connected with the 4 end of the diac DB 1. And the other end of the capacitor C4 is connected with the 4 end of the diac DB1 at the connection point of one end of the capacitor C4 and the 4 end and the 5 end of the leak point protector U2. The connection point between the leakage protector U2 and the capacitor C6 is connected with one end of the capacitor C5, and the other end of the capacitor C5 is connected with the 4 end of the diac DB 1. In other words, by matching the diac DB1 with the first thyristor Q1 and the second thyristor Q2 described above, the overvoltage in the leak protection circuit 100 can be effectively reduced.

In one embodiment, the switch 30 is a relay, the coil of which is responsive to a control signal such that the contacts of the relay are open; wherein the contacts of the relay are arranged in the line between the live and neutral wires and the load.

Specifically, as shown in fig. 1, the switch 30 is a relay J1, one end of a coil of the relay J1 is connected to the 2 end of the diac DB1, the other end of the coil of the relay J1 is connected to a live wire, the 3 end of the diac DB1 is connected to a neutral wire, contacts of the relay J1 are disposed on the live wire and the neutral wire, and when the coil receives a control signal, i.e., is energized, the contacts of the relay J1 are opened. A diac may be connected across between the 2 terminal of diac DB1 and the 3 terminal of diac DB 1. In other words, by providing the relay J1, it is possible to realize automatic disconnection of the line between the live wire and the neutral wire and the load in the case where leakage current is generated in the live wire and the neutral wire.

While certain specific embodiments of the utility model have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the utility model. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the utility model. The scope of the utility model is defined by the appended claims.

Claims (8)

1. A leakage protection circuit, the circuit comprising:

the triggering module responds to leakage current generated between the live wire and the zero wire and outputs a triggering signal;

the control module is used for responding to the trigger signal and outputting a control signal; and

and the switch is arranged in a line between the live wire and the load as well as between the zero wire and the load, and is opened after responding to the control signal.

2. The leakage protection circuit of claim 1, wherein the trigger module comprises a current transformer, and an iron core of the current transformer is sleeved on a line between the live wire and the zero wire and a load;

the iron core of the current transformer responds to leakage current generated between the live wire and the zero line, so that the winding of the current transformer outputs a trigger signal.

3. The leakage protection circuit of claim 1, wherein the control module comprises a leakage protector and a thyristor sub-module;

the leakage protector responds to the trigger signal and outputs a conduction signal;

and under the condition that the thyristor submodule is turned on after responding to the on signal, the leakage protector outputs a control signal.

4. A leakage protection circuit according to claim 3, wherein the thyristor sub-module comprises a first thyristor and a second thyristor;

the leakage protector responds to the trigger signal and respectively outputs a first conduction signal and a second conduction signal;

the leakage protector outputs a control signal in a case where the first thyristor is turned on in response to the first on signal and the second thyristor is turned on in response to the second on signal.

5. The leakage protection circuit of claim 4, further comprising a first resistor and a first capacitor connected in series, and a second resistor and a second capacitor connected in series;

the other end of the first resistor is connected with the anode of the first thyristor, and the other end of the first capacitor is connected with the cathode of the first thyristor;

the other end of the second resistor is connected with the anode of the second thyristor, and the other end of the second capacitor is connected with the cathode of the second thyristor.

6. A leakage protection circuit according to claim 3, wherein the leakage protector model is M54123L.

7. The leakage protection circuit of claim 1, wherein the switch is a relay, a coil of the relay being responsive to the control signal to cause contacts of the relay to open;

the contact of the relay is arranged in a line between the live wire and the zero wire and the load.

8. The leakage protection circuit of claim 1, wherein the switch receives the control signal via a diac and opens in the event the control module outputs the control signal.

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